Ultra-sensitive acrylamide detection in potato chips extract based on carbon paste electrode modified with liposomes carrying ferrocene-labeled aptamer.

Abstract

The rapid and sensitive detection of acrylamide in thermally processed food products has attracted significant scientific interest. Herein, we report a novel electrochemical aptasensor that integrates a ferrocene-labeled DNA aptamer within a liposome-based nanostructured interface for enhanced signal transduction. The sensing layer was constructed by embedding the ferrocene-modified aptamer into didodecyldimethylammonium bromide (DDAB) liposomes and immobilizing the resulting system onto a carbon paste electrode, providing an innovative platform that combines biorecognition with redox-active nanocarriers. The liposomes were characterized in terms of zeta potential, hydrodynamic diameter, and polydispersity index, confirming their stability and effective aptamer incorporation. Detection is based on target-induced modulation of the ferrocene redox signal, monitored by square wave voltammetry (SWV). The aptasensor exhibited a decrease in ferrocene current upon acrylamide binding over a concentration range of 0.01-100 nM, with limits of detection of 0.25 nM in buffer and 0.30 nM in spiked potato chips extract. High selectivity was demonstrated against potential interfering compounds, including asparagine, glucose, and glycine. The sensor retained stable performance for at least 7 days. Applicability in complex food matrices was confirmed by satisfactory recovery values. The proposed platform introduces a novel liposome-mediated signal transduction strategy that extends beyond conventional aptasensor architectures, offering improved control over probe organization and redox response. This approach provides a versatile design framework for next-generation electrochemical aptasensors and shows strong potential for sensitive and selective monitoring of acrylamide in food samples.